These are ombre-styled brows! They gradate from a lighter shade to a darker shade, creating a nicely shaped, obviously colored in brow. It's still pretty, though. They come in 6 colors that match the main hues of the base game hair textures, so you won't have awkwardly colored eyebrows. They also match better with the hair meshes in the Sims 4, as it is more of a cartoony sort of style. They are simple enough to always look fabulous in-game.
Additional Credits:
Smaller Eyelashes by Vampire_aninyosaloh (I used the lighter ones so you may not be able to see them, they build up with the main lashes to create a fuller lash)
Big False Eyelashes by -Shady-
Skin by Chisami
Eyes by -Shady-
Lipgloss by me
This is a Maxis Recolour which means that it is a recolour of an item that already exists in your game. Please check the Pack requirements to see which game pack it recolours.